Back and leg pains are known as common complaints in medicine. According to National Institutes of Health figures, approximately seven million people were under a physician's care for low back pain in the United States in 1971. Early in this century, mechanical back pain syndromes involving the sacro-iliac and lumbar facet joints were well documented. It was then believed that all back and leg pain was due to mechanical factors. Not until 1934 was the degenerative etiology of intervertebral lumbar disc herniation and its relation to back and sciatic pain accurately recognized.
When a herniated disc produces significant neurologic deficit by compression of an anterior primary nerve root, physicians consider surgical decompression the proper treatment. The great majority of degenerative disc cases, however, are less serious and more conservative treatment is indicated prior to the consideration of surgical intervention.
It has been observed that most patients with protruded lumbar discs and insignificant neurologic deficit can be effectively cured by two to three months of complete bed rest. Major problems of instituting such therapy include the social and economic impact of incapacitating a wage earner or active household head for such a long period of time. It appears that many discectomies may be performed for the purpose of expediency alone to avoid such prolonged incapacitation. The therapy and apparatus of this invention achieves the desired beneficial result without surgery or extended periods of incapacitation.
When back surgery is performed, failure rates are variously estimated as being between 10% and 40%. Painful "failed back surgery syndrome" due to scarring adhesions of the arachnoid and nerve fibers of the cauda equina in the lumbo-sacral area is common. There is thus a need for more effective means of short term, conservative therapy for patients with lumbar degenerative disc disease associated with disc protrusion for whom surgery is not immediately indicated, and for those suffering from failed back surgery syndrome who can be helped by stretching or loosening scar tissue, which need is met by the apparatus and method of this invention.
Known traction methods such as Buck's and pelvic traction, have traditionally been used in an effort to achieve distraction or reduction of the lumbar spine. It has recently been shown by Dr. A. Nachemson, in "The Load On Lumbar Disc In Different Positions Of The Body", Clinical Orthop, 45: 107-122, that even in the relaxed supine position, there is loading of a normal lumbar disc. In moderately degenerated discs the vertical load on the annulus fibrosus is higher than normal. It is unlikely that conventional known traction can achieve true lumbar reduction by producing negative pressure on the disc interspaces.
Various stretching techniques have also been tried over the years with limited success because the human body is better able to tolerate and compensate for stress applied gradually over a period of time, than the sudden application of high forces.
Negative loading of the lumbar spine may be achieved by supporting the upper body above the lumbar spine as by the chest, sides or under the arms and allowing the lower body to hang under the force of gravity. A device for supporting the upper body while the lower body depends in a vertical position at 90.degree. to the horizontal is disclosed in U.S. Pat. No. 3,353,532 issued to L. C. Ellison on Nov. 21, 1967.
The inventor of the present apparatus and method supervised construction of apparatus, in 1971, to support a patient with a protruded lumbar disc in a vertical, non-inclined or fully dependent position by a chest harness. The device was utilized during the day for ten days following which the patient became asymptomatic. However, hanging in a fully dependent position is acceptable only to a few strong patients. Depending on the construction of the supporting means, unnatural loads may be applied to the chest, sides or shoulders, which stresses are particularly hard on an already weakened patient. For a patient suffering from failed back surgery syndrome, such hanging can result in such a dramatic increase in pain that it may be impossible for the patient to tolerate.